Forestregeneration

Forest Regeneration Handbook
Editors:
Jeffrey S. Ward
TheConnecticutAgricultural
ExperimentStation,NewHaven
Thomas E.Worthley
UniversityofConnecticut,
CooperativeExtension
Contributors:
TheConnecticutAgricultural
Experiment Station
Sharon M. Douglas Plant Pathology and Ecology
Carol R. Lemmon Entomology
Uma Ramakrishnan Forestry and Horticulture
J.P. Barsky Forestry and Horticulture
Department of Environmental Protection
Martin J. Cubanski Division of Forestry
Peter M. Picone Wildlife Division
Funding provided by
U.S. Forest Service, Northeast Area, State and Private Forestry
The Connecticut Agricultural Experiment Station, New Haven
University of Connecticut, Cooperative Extension
Connecticut Department of Environmental Protection
A guide for forest owners,
harvesting practitioners,
and public officials
Production editor and layout: Paul Gough Graphics: Jeffrey S. Ward

2 REGENERATION HANDBOOK
Forests are dynamic. Seedlings germinate, grow, compete with
each other and with larger trees. Some survive for hundreds of
years. Change will happen. Which species will be predominant
in the future forest depends not only on climate and soils, but
also on management decisions made today. Changes in forest
composition will affect the quality and variety of forest
resources available to future generations and wildlife.
This handbook was developed to provide an appreciation of how
our forests developed and an understanding of forest regeneration
concepts,includingtheimportanceofdisturbance. Thisinformation
willhelplandownersandpublicofficials,inconcertwithprofessional
foresters,makeinformeddecisionsaboutforestregenerationoptions
tailoredtotheirmanagementobjectives.
Thishandbookisdividedintofivesections.
• The first section provides a short history of the forest from the
periodofEuropeancolonizationandlargescalelandclearingthrough
the present suburban forest. It concludes with the challenges
(fragmentation,parcelization,deer,invasivespecies)thatmustbemet
tomaintainahealthyandvibrantforestforfuturegenerations.
• The second section explains basic concepts in forest
regeneration. Theimportanceofdifferentcombinationsoflight,
moisture,andsoilindeterminingsuccessorfailureofregenerationis
discussed. It then details the adaptations of different species to
distinctcombinationsoflight,moisture,andsoilconditions. The
sectionconcludeswithanexaminationofcompetitiveinterference
among trees striving to form part of the upper canopy.
•Thethirdsectionexaminestheroleofdisturbanceinmaintaining
habitatandspeciesdiversity. Theinfluencedistinctdisturbance
regimeshaveonforestcompositionisalsoexplored.
•Thefourthsectionintroducesdifferentmethods(prescriptions)
offorestmanagement. Theinfluenceofeachmanagementstyleon
theavailabilityoflight,moisture,andgrowingspacefornew
regenerationisdiscussed. Becausetheprimaryreasonforharvesting
isofteneitherincomeoranon-commodityamenitysuchaswildlife,
theeconomicandestheticconsiderationsofeachmanagement
method are also presented.
•Thehandbookconcludeswithasectiondetailing requirements
to successfully regenerate specific species. As with the other
sections, this section is not intended to be an authoritative reference,
butrathertoprovidereaderswithsufficientinformationtomake
informeddecisionsaboutforestmanagementoptions.
Introduction

3REGENERATION HANDBOOK
Table of Contents
Connecticut’s Forest .......................................................................4
Ashorthistory .................................................................................................4
The forest resource..........................................................................................6
Thechangingforest..........................................................................................7
Challenges Today and Tomorrow .................................................9
Limiting Factors ........................................................................... 12
Lightandspace .............................................................................................13
Soil ...............................................................................................................14
Moisture .......................................................................................................15
Sitequality ....................................................................................................16
Competition ..................................................................................................17
Standdevelopment ........................................................................................18
Disturbance the Agent of Change .............................................. 19
Type .............................................................................................................21
Intensity ........................................................................................................22
Frequency .....................................................................................................23
Forest Management..................................................................... 24
Forest preserve .............................................................................................25
Single-treeselection.......................................................................................26
Shelterwood..................................................................................................27
Silviculturalclearcutting ..................................................................................28
Groupselection .............................................................................................29
Coppice with standards .................................................................................30
Reserve tree ..................................................................................................31
Diameterlimit/high-grading.............................................................................32
Species Regeneration Notes ....................................................... 33
Oak ..............................................................................................................34
Maple ...........................................................................................................36
Pine ..............................................................................................................38
Birch .............................................................................................................40
Beech ...........................................................................................................42

Viewed across the landscape, the forests covering our hillsides
and valleys seem as though they have always been there.
A different story emerges, however, when walking along a trail
and evidence of human impact on the land from earlier
generations is discovered. Overgrown stone walls outline old
pastures and grain fields. Occasionally, the outline of a charcoal
mound or a sunken cellar of a farmhouse can be found. The
landscape has undergone dramatic changes since European
settlement including large-scale land clearing for agriculture,
wildfire, hurricanes, and repeated harvesting. The following
pages chronicle the dynamic and resilient nature of the
Connecticut forest over the past 400 years with a special
emphasis on disturbances and changes in land use patterns.
AShortAccount of a Long History. When the Dutch and
EnglishbegantosettleinConnecticutaround1633,itisestimated
that 90-95% of Connecticut was covered with forest. The colonists
gradually cleared the land to plant their crops and orchards, create
hayfields,anddeveloptowns. Inaddition,theyharvestedthevirgin
forests to provide timber and firewood for domestic use and export.
In 1710, the English Parliament passed the White Pine Act to
protect the large white pines needed for masts for the royal fleet. It
is interesting to note that an act about forest use was one of the first
to contribute to the dispute between the colonists and the British
Empire, that led to the American Revolution. It may be hard to
believe, but by the mid-1800s, 75% of the state had either been
converted to pasture or was plowed for food production.
The remaining quarter of the state that was forested was not like
the forest we know. The forest provided wood for homes, furniture,
wagons, tools, and fuel. Hickory was prized for tool handles, and
hickory smoke added a distinctive taste to cured meats. Rot-
resistantchestnutpoleswereusedforfencesandbuildings.
Sassafras was used as a teak substitute on ship decks, and, because
of its reputed power to repel insects, was used to make beds and
chicken coops. An even larger part of the forest was cut for wood
to cook meals and heat houses through the cold New England
winters. Undoubtedly,manyearlyAmericanssupplementedtheir
dietswithfoodsfromtheforestsuchasAmericanchestnuts,maple
syrup, blueberries, and game. These foods added variety to their
dietsandhelpedthemsurvivethelongNewEnglandwinters.
In the mid-to-late 1800s, many farm families moved west to
Connecticut’s Forest

establishnewfarmsonthemorefertilesoils,leadingtothe
abandonmentofmanyConnecticutfarms.Otherfamiliesmovedto
themilltownstoearnahigherincomethancouldbegainedon
hardscrabble and overworked farmlands. The abandoned farms
quickly converted to young forests of hardwood and pine.
The last great cut of our forests came in the late 1800s. Entire
hillsides were cut to produce charcoal and fuelwood, not only for
home use, but also for the local brick, brass, and iron industries.
Stands were typically cut every 20-40 years when the trees were still
smallenoughtobehandledmanually. Charcoalproductionfell
dramatically in the early 1900s with the advent of cheap coal and
petroleum. Most of the forest we see today has its origin in the
charcoal-production era and consists of even-aged stands.
During the early 1900s, immense fires, covering up to 20,000
acres, regularly roared over the countryside. Some of these were
accidental, caused by escaping sparks from railroads, homes, and
industry. Records from the early 1900s indicate 15,000 to over
100,000 acres (in 1915) of forest fires in Connecticut. This wanton
destruction of forest resources spurred the legislature to create the
position of State Forest FireWarden in 1905 to coordinate fighting
of forest fires. The efforts of state and local fire fighters has reduced
the annual amount of forest damaged by wildfires to an average of
1,300 acres in recent years.
Impactstotheforesthavenotbeenlimitedtoclearing,cutting,
andburning. Priortotheimportationofthechestnutblightfungus,
upwards of 25% of our forest was comprised of American chestnut
trees. Gypsy moth outbreaks defoliated large swaths of the state
between 1960-1990. Another species that has also been affected
byinsectsanddiseaseincludeeasternhemlock,currentlythreatened
bythehemlockwoollyadelgid.
Historicalrecordssuggestthatseverehurricanesstrike
Connecticut every 100-150 years. It was estimated that the 1938
hurricane destroyed over 100,000 public shade trees, every mature
whitepinestandeastoftheConnecticutRiver,andalmostone-fifth
of the timber in the state. Nearly 55,000 acres of forest were
flattenedand45milesinlandnearPutnam,saltdamagewas
observed. Other weather events that have caused widespread forest
destruction include ice storms (1898 and 1921), microbursts, and
tornados such as the one that destroyed the Cathedral Pines in 1988.

The Forest Resource. Asignificant local forestry products
industry has developed in the past several decades to utilize our
maturing, but renewable, forest resource. Steve Broderick of the
UniversityofConnecticutCooperativeExtensionSystemhas
reported that there are over 350 forest product firms in Connecticut
employingapproximately3,600people. Thesecompaniesharvested
anaverageofnearly90millionboardfeetoftimberannuallybetween
1985 and 1998. Connecticut companies manufacture products
rangingfromfinefurnituretoshippingpallets,fromcabinetsto
charcoal, and from doors to wood mulch. In addition, each year the
Connecticutforestyields15,000gallonsofmaplesyrupandalmost
alloftheworld’ssupplyofwitchhazelextract.
ThevalueoftheforesttoConnecticutismuchmorethansimply
the timber and other forest products. First and foremost, forests
protect watersheds, aquifers and groundwater supplies that provide
the bulk of our clean drinking water. Trees can also provide air
pollutioncontrol,actingasgiantspongestoremovedust,
particulates, and some airborne chemicals. In addition, trees cool
ourenvironmentinthesummerbyrecyclingwaterandreflecting
sunlight.
Forests contribute to the character of Connecticut and the
$3.9 billion tourist industry. People come from all over the country,
from all over the world, to view the kaleidoscope of fall colors that
we sometimes take for granted. Healthy forests add to our
enjoyment during other times of the year. We mark the end of winter
bynotingthefirstpussywillowflowers. Treesshadeourhomesand
picnicsinthesummerwhilewhitepinesamplifythewhistlingofthe
wind. Massive oak and yellow poplar tree trunks lend a sense of
wilderness to modest urban parks.

The Changing Forest. The past 300 years has seen the many
changes in the landscape: from a sea of forested hills to a quilt of
agriculturalfieldsandwoodlots,fromabandonedfarmstoshort-
rotation forests cut for firewood and charcoal, from burned over
standstomatureforestsincreasinglyfragmentedbyencroaching
suburbandevelopment.
InConnecticutforestsandinmanynortheasternandAppalachian
forests, we are at the beginning of a second major successional
change in forest composition in 100 years. Since the loss of
American chestnut in the early 1900s, the Connecticut forest has
been dominated by oak.Agradual conversion of our forest from oak
to other species, such as maple, birch, and beech has taken place at
a rate of approximately 5% every decade since 1938. Connecticut’s
oak forests could slowly disappear in the next
100yearsifthistrendcontinues.
Aswiththeshiftfromchestnuttooakforestsatthebeginningof
the century, the emergence of a forest dominated by northern
hardwoodswillaltertheeconomic,ecological,andestheticvaluesof
our forest. The consequences of these changes will last well into the
21st Century. Oak is more economically important than maple and

birch for its higher value, lower cull rates, and higher per acre
volumegrowth.Theshiftfromoakwillalsoaffectmanywildlife
andinsectpopulations--discriminatingagainstthosespecies
dependent on oak and favoring those species associated with
northernhardwoods.
Changes in esthetic values are important because of increased
publicutilizationoftheforestedlandscapeforbothhomesitesand
recreation. The leaves and flowers of maple and birch are more
colorful than oak. However, faster -growing oaks and pines are
morelikelytohavethe“bigtree”characteristicsthatthepublic
associates with mature forests. Changes made to the land by
modern society tend to be much more permanent than those made
in the past. Cut-over, burned, or converted to pasture, the forest
always grew back. The same cannot be expected from the
conversions made to other land uses today. As an ever-growing
populationdemandsanever-increasingarrayofbenefitsfroma
continuallyshrinkingforestlandbase,carefulstewardship,
including the need to be able to successfully regenerate the forest
with desirable species, becomes ever more critical. Our society is
poised at a unique moment in history, with respect to the future of
the forest resource, and the decisions we make today will affect
whethermanyfuturegenerationswillcontinuetoenjoythevast
benefits our forest resource provides.

Whether landowner, professional forester, or concerned citizen,
we must remain united in our commitment to sound forest
management based on the best available science to avoid a
return to the sad state of our forests during the mid-1800s. Five
major challenges to forest management at the landscape level
can be recognized in Connecticut. These are: invasive species,
coping with deer, fragmentation and parcelization, maintaining
habitat diversity, and the stewardship of private forestlands.
Alien (Non-native) Invasive Species. Alien invasives have
interruptednaturalplantassociationsandecologysincethetimeof
Europeansettlement.Settlersimportedthesespeciesfromtheir
homelands for their one or two desirable characteristics. They were
unawareof,ordidnotconsider,theirinvasivepotential.
Theintroductionofalienplantshasnotonlycausedthe
displacementofnativeplants,butindirectlycausedproblemsby
bringinginalienfungiandinsects.
Coping with Deer. White-tailed deer are very adaptable, and
can survive in forest stands in all stages of development. The current
highdeernumbershavesignificantlyalteredtheforeststructurein
Connecticut. Deer browsing affects regeneration, abundance and
distribution of species. Forage is best from stands in early stages of
succession,wheretheforestfloorisopentosunlight.
FragmentationandParcelization.Amajorissueplaguingthe
forest resource of southern New England is population growth and
the associated loss of forested open space to residential
development.Inasteadilysuburbanizingregion, privately-heldland
can be subject to change in ownership and use at any time. Change
inuseandownershipcanaffectallmembersofthecommunityand
should be planned, or at least anticipated, in order to minimize the
impacttobothhumanandforestcommunities.Throughadetailed
inventoryandanalysisofnaturalresourcesinacommunityand
educationaloutreach,localplannersanddecisionmakerscanobtain
thedatatheyneedtomakeeffective,highqualityplansfor
conservationanddevelopmentthatwillguidefuturegrowthintheir
towns.
Inaddition,byrecognizingtheimportanceoftheuplandforest
resources in protecting water quality, wetlands and other habitat
features,communityleaderscanjustifytheeffortnecessaryto
determinetheextentanddistributionofforestedlandandidentifying
areas most suitable for protection and sensitive areas that may be
threatenedbydevelopment.
Challenges Today and Tomorrow

Maintaining Habitat Diversity. The value of the early
successionalhabitatfoundinseedling/saplingstandsforamyriadof
plantandanimalspeciesisnotwellappreciated.Unfortunately,
Connecticuthasbeenlosingthesevaluableearlysuccessional
habitats at an alarming rate attributable to three factors. 1) These
habitats are ephemeral. The very nature of plant and tree growth
causes them to change to more advanced successional stages.
2) Fewer farm fields are being abandoned and those that are
abandoned are often converted to new development. 3) Partial
cutting(uneven-aged)hasbecomethedominantforestmanagement
practice. Whileitisunlikelythatearlysuccessionalhabitatwill
completelydisappearfromConnecticut,itwouldbeworthwhileto
determine thecriticalminimumamountofearlysuccessionalhabitat
requiredtomaintainhealthypopulationsofearlysuccessional
species.Uneven-agedmanagementoftenhassignificantlylower
visualimpactthaneven-agedmanagementpractices,butcan
accelerate the replacement of oak by birch, maple, and beech.
Private Lands Stewardship. The stewardship of forests on
private lands needs to be a concern for landowners, local land-use
officials and forest practitioners. Of the 60% of Connecticut that is
forested,approximately85%isinprivateownerships.Someprivate
lands are managed by land trusts, small water companies, camps,
andsportsmen’sorganizations.However,thebulkofprivate
landownersareindividuals,families,andfarmers.Whileforestland
ownership patterns and owner’s goals are varied, diverse, and
complex,therearesomeemergenttrendsandidentifiablepatterns,
whichmayprovideanindicationaboutthelong-rangefutureofthe
forest resource.
Forestlands are becoming increasingly parcelized: Although
the amount of forested land has remained remarkably stable over the
last 30 years, the number of different owners has increased
dramatically.As ownership changes hands, large parcels are often
dividedintopiecesthatarestilltechnicallyforestland,butare
economicallyandlogistically“unmanageable”forallpractical
purposes. Over 75% of forested properties in Connecticut are
parcels less than 10 acres in size.
Landowners are aging and lots of land will change hands in
the next 15 years: The average age of forest landowners, for
parcels greater than 10 acres, is somewhere in the early 60s. As
current owners approach the end of their tenure, property is often
soldoffortransferredtootherfamilymembers.

Thisprocesscontributessignificantlytoparcelization,leadingto
fragmentationofresource.
Demand for benefits from the forest will increase: Asteadily
increasingpopulationwilldemandanever-increasingsupplyof
products and other benefits from a steadily decreasing forest land
base. Benefits derived from private forests that contribute to the
economyandtheoverallqualityoflifeinoursocietyincludethe
followingbroadcategories:
Recreation – access, sites, facilities, and diverse opportunities
Habitat– private holdings provide the bulk of necessary habitat
Watershed protection – private forests protect most of the
source-water areas for surface waters, groundwater and aquifer-
recharge areas
Forest Products – 75%+ of the raw material for a $700 million
forestproductsindustrycomesfromprivateforestlands
Aesthetics – the forest in Connecticut is considered to be the
essentialbackdropforthetourismindustry
Landowners receive no benefit in return for many of the
benefits they provide:The public enjoys many benefits derived
fromprivateforestlandsthatarepublicinnature,highqualitywater,
cleanerair,wildlifehabitat,andaesthetics,forexample,andoften
take them for granted, at no cost. The people who own and manage
the resource are not directly compensated for the public benefits to
whichtheirlandscontribute.
Few, if any financial incentives exist for holding forestland,
except forest products: Landowners often hold forest lands for
reasons other than the promise of economic return, but often some
economic return is necessary in order to keep the land “intact.”Trees
sold as raw material for forest products are often the only potential
sourceoffinancialsupportfortheland.
Managing the forest for periodic income from the sale of
trees as raw material for forest products DEPENDS on being
able to regenerate the forest successfully: When trees are
harvested,theabilitytoreplacethemwithadesirablemixofhealthy
andproductiveseedlingsnaturallymaintainsthevalueoftheforest.
Therefore,landownerswhomanagefortimberincome,loggersand
otherforestpractitionerswhodependonagraduallyshrinkingland
base for their livelihood, need to be invested in the knowledge of
howtoinsuresuccessful,desirableregeneration.

Trees and stands of trees are able to survive and grow under
unique combinations of environmental conditions (e.g.,
nourishment, moisture, light and space). Different types of trees
or stands require different combinations of these factors
depending on their particular adaptations. Healthy, productive
stands are those in which these factors are found in appropriate
quantities for optimum growth and development for the species
mix in question.
When one or more factors are in short supply the growth and
development of the tree or stand is affected. Where a serious soil
moistureshortageexists,forexample,increasingtheabundanceof
light,spaceorsoilnutrientswouldnotlikelyincreasethegrowthrate
of trees at that site.As soil moisture is increased, however, a
corresponding increase in the growth and development of the stand
couldbeexpecteduntilsomeotherfactorbecomeslimiting.
The manner in which these factors interact at the scale of the
seedlingwilldeterminetheabilityofseedlingstogerminate,become
established,survive,andgrow. Amongthefactorsaffectinggrowing
conditionsatanysite,theonethat,ifincreased,willresultinthe
greatestcorrespondingincreaseinproductivityofthestand,is
consideredtobethe“mostlimitingfactor”.
Limiting Factors
ABIOTIC FACTORS BIOTIC FACTORS

LightandSpace.Allgrowingplantsrequiresunlightfor
photosynthesis…trees included! For most tree species in the
Northeast,lightavailabilityisthemostlimitingfactortosuccessful
regeneration.Speciesthatcompetebestinfullsunlighthavethe
capacity for rapid height growth and are often found in the upper
layers of the forest canopy. Species that are able to compete in the
shade of other trees can occupy lower layers in the canopy, and each
canopylayerwillinterceptadditionalsunlight.
Theminimumamountoflightrequiredforoptimumgrowthand
development(orevensurvival!)variesdramaticallyamongtree
species.Therelativeminimumrequirementforsunlightisknownas
“shadetolerance”.Theshadetoleranceofseedlingsisakeylimiting
factorintheirdevelopment.Disturbanceinastandwillstimulate
regeneration.Whenmanagementobjectivescallforregeneratinga
matureforest,forestersplanharvestingsystemstocontrolthelight
availability,dependingonthedesiredmixofseedlingspecies.
Limiting Factors
(Needs full sunlight)
Tulip-poplar
Paper/gray birch
Bitternut/mockernut/hickory
Aspen
Ash
Pin cherry
SHADETOLERANCE
Midtolerant Shade tolerantShade intolerant
(partial sunlight)
Red/black/scarlet oak
Shagbark hickory
White/chestnut oak
White pine
Black/yellow birch
Pepperidge
(forest shade)
Hemlock
Sugar maple
Beech
Basswood
Stripe maple
Red maple
SPECIES CHARACTERISTICSANALOGY
Shade intolerant
High stakes gambler
Fast growth rate
Few reserves
Short life span
High mortality
Midtolerant
Investor
Moderate growth
Some reserves
Medium life span
Moderate mortality
Shade tolerant
Miser
Slow growth rate
Large reserves
Long life span
Low mortality

Soil – “Back to Our Roots…” Taken together the root systems
of trees in the forest comprise a complex interwoven carpet of live
woodytissueintheupperlayersofthesoilthatisdynamic,growing
and ever changing. Spring and fall are the most active periods of
root growth.
Therootsystemsoftreesprovidefouressentialfunctions:
1) anchorage or support, 2) storage of nutritional compounds,
3) absorption of water and nutrients, and 4) conduction of water
andnutrients.
Ninety percent or more of tree roots are found in the top foot of
soil because roots need oxygen to survive. Because most roots are
near to the surface, they are susceptible to damage from heavy
equipment,especiallywhensoilsarewet.
Soil Structure and Fertility. Soil characteristics are equally
importanttocanopydisturbanceininfluencingforestcompositionin
Connecticut. Not all soils are the same; in fact, it is amazing how
manydifferentsoiltypesthereare,eachwithitsownpeculiar
characteristics.Themixofsoilfertility,moisture,andtexture
determinewhetheraspecieswillthriveonanygivensite.
Avarietyofsoilnutrientsmustbepresentinavailableformfor
seedlings to be successful. Elements such as carbon, nitrogen and
hydrogenusuallycyclethroughtheorganicmaterialpresentinthe
forest,whilepotassiumandphosphorouscomefromthemineral
portionofthesoil.Seedlingsalsorequireavarietyofminornutrients
suchascalcium,iron,andsulfur.Eachplaysaroleinthelifecycleof
the tree and must be present for survival and successful growth. In
short supply, one or more nutrients can be the limiting factor to the
growth and development of trees or stands.
ProtectingSoil.Protectingthesoilduringanyforestmanagement
practice is both the law and a moral obligation. Every forest
managementactivityfromtrailconstruction,tofirewoodcutting,to
regeneration harvests in mature forests must be conducted in a
mannerthatdoesnotresultinexcessivedetrimentaldisturbancesto
theforestsoil.Limitingsedimentationoferodedsoilinstreamsisa
primaryconcernofforesters.
Properlyconductedharvestingoperationswillnotonlycontrolthe
amountofsunlightreachingtheforestfloor,butleavethestandwith
soilconditionsthatareidealforpromotingsuccessfulregeneration.
Limiting Factors

Soil Moisture. Forests have a remarkable capacity to absorb
stormwater, regulate stream flow, and clean water as it moves
through the forest ecosystem. Compared to other land uses, forests
areexcellentlandcoverforprotectingwaterquality.Theinteractions
between the forest soil, moisture, and seedlings when forest stands
are harvested and regenerated can best be understood by examining
howforestsandwaterinteractinundisturbedenvironments.
Whenprecipitation(rainandsnow)fallsonanundisturbedforest,
much of it never reaches streams and underground aquifers. Some is
caught on the leaves and branches and evaporated back into the air.
Some of the rain that reaches the ground is absorbed by tree roots
andiseventuallytranspiredintotheairthroughtheleaves.Together
these processes are known as evapotranspiration.
Evapotranspiration can account for one-third or more of the annual
precipitation.
Theundisturbedforestfloorconsistsofathicklayerofleaflitter
on top of a loose friable soil that is high in organic matter and
securely bound by tree roots. It has a tremendous capacity to
absorb rainfall. Overland flow or runoff is a rare event in the forest,
andsignificanterosionisvirtuallyunheard-ofinundisturbedforests.
Instead, clean water gradually percolates through the soil to the
groundwater,oreventuallyemergesinstreams,pondsandwells.
Species/Moisture Relationships. Each species has adaptations
for distinct moisture regimes. Some species have adaptations for
extended periods of drought (e.g., pitch pine, chestnut oak). Other
species are adapted for extended flooding (e.g. silver maple, pin
oak). Saturated soils and surface water present unique challenges
for trees because roots need to breathe. Most species grow in the
continuum between very dry and very wet soils. Our most valuable
timber species tend to thrive best on moist, well-drained soils.
Seedlingsofanyparticularspecieshaveawelldefinedrangeofsoil
moistureinwhichtheyhavethegreatestcompetitiveadvantage.
Limiting Factors

Site Quality – Putting itAllTogether. The natural vegetative
cover for most of Southern New England is forest of one type or
another,andwhilethismaygenerallybethecase,itiscertainlytrue
that some sites are better for growing forest trees than others. Tree
growthisafunctionoftheparticularcapabilitiesofthespecies,
primarilygenetic,interactingwiththeenvironmentwherethetreeis
located.Theenvironmentalfactorsassociatedwiththemoisture,soil
fertility,anddrainagedescribedearlierarecollectivelyknownasSite
Quality. Obviously, perhaps, a site that has favorable conditions for
treegrowthisconsidered“good”,whileasitewithconditionsthat
inhibitgrowthwouldbeconsidered“poor”.
Lessobvious,perhaps,isthefactthatenvironmentalconditions
considered favorable for one species may be unfavorable for
another, so any discussion of site quality must be made in the context
of a particular species or species mix (forest type). In Connecticut,
trees grow almost everywhere except on solid rock and in areas of
permanentstandingwater.
Limiting Factors
Poorsiteshavelowfertilityand
drysoils.Theyarecommonly
found on ridgetops, swamps,
and where soils are very sandy
Averagesiteshaveintermedi-
atesoilmoistureandfertility.
Theyarecommonlyfoundon
hillsides.
Goodsiteshavehighfertility
andabundantsoilmoisture.
Theyarecommonlyfoundin
valleys and lower slopes or
benchesonhillsides

Limiting Factors
Competition Overview. New seedlings for most species in
SouthernNewEnglandoriginatenaturallyfromoneoftwosources:
germinating seeds or sprouts from stumps or roots. Successful
naturalregenerationdependsupontheavailabilityofanearbyseed
source for the desired species and/or a sufficient number of sprouts
from stumps or roots. As a rule of thumb, the older trees are when
harvested, the less their ability to produce root or stump sprouts. So
followingharvestinginmaturestands,regenerationofdesiredspecies
is not likely to occur without a reliable source of seeds nearby. It is
very important to remember that when the overstory of a stand is
onlypartiallyremoved,thespeciesthatcomprisetheresidualstand
will also be the predominant seed source for the new forest that will
grow to replace the old.
Onceestablished,seedlingsmustcompeteforlight,moisture,
nutrients, and space, not only with other tree seedlings, but also with
shrubs, grasses, and herbaceous plants. Only rarely do certain
species, such as American beech and eastern hemlock, have the
naturalabilitytogerminate,surviveandcompeteinheavyshade.
Many species require abundant light in order to survive and grow.
Biotic Competition – Diseases. Diseases have historically
playedanimportantroleinforesthealthandwillcontinuetoimpact
forest regeneration. Because forest diseases, in general, cannot be
easilycontrolled,theirimpactistolimitthechoiceofspeciesthat
maybesuccessfullyregenerated.
Biotic Competition – Insects. As with forest diseases, insect
pestsoftenlimitspecieschoiceswhenregeneratingforests. The
naturaldefensemechanismsofseedlingsdeclinewhentheybecome
stressed and weakened due to factors such as the change in
microsite conditions (light, moisture, etc). Stressed trees are more
susceptible to insect pests.
See descriptions of diseases and insects in the web version
Control of Competing Vegetation. Agood vegetable gardener
would never expect to grow tomatoes without ever pulling weeds,
andmanagingaforestforsuccessfulregenerationcanbeviewedin
muchthesameway.Removingthecompetingvegetationislike
pulling the weeds to help the desired plant or tree grow.
When planning a harvest of overstory trees it is important to
considerreducing competitionfromundesirableunderstory
vegetationifthedesiredregenerationistobesuccessful.Thismight
involve extra time and expense, but this step is essential to insure the
success of desired regeneration.

Stand Development–Regeneration Bottlenecks.
Conditionschangerapidlywithinaforeststandduringearlystand
development, and the success or failure of a new stand of desirable
regeneration rests on its ability to overcome certain barriers, or
“bottlenecks”. Regeneration bottlenecks can be categorized
accordingtotheperiodofearlystanddevelopmentduringwhich
theymayhavethemostinfluenceonthedesiredregeneration
species.
Unmanaged forests in Connecticut typically have 5,000 to 12,000
seedlings and saplings per acre. Regeneration densities can soar
upwards beyond 30,000 stems/acre several years after harvesting.
Theseestimatesdonotincludeuntoldnumbersofshrubs,ferns,
grasses, and herbaceous plants. At the beginning of canopy closure,
when crown classes can be distinguished, fewer than 2000 stems/
acre remain in the upper canopy.
StandInitiation.Itisimportanttorealizethatonlyregeneration
that is established by the end of the first growing season after a
disturbance (such as harvest) has any chance of forming a part of the
futureforest.
Thetimingofaharvest,theprovisionforareliableanddesirable
source of seeds or sprouts, and the preparation of a suitable
seedbed are factors that must be incorporated into a management
systemtosuccessfullyobtainregenerationconsistentwiththe
landowner’sobjectives.
Establishment. During the 3 to 4 years following that critical
firstgrowingseason,trees intheyoungstandmustcompetewith
eachotherandothervegetationforsunlight,moisture,andnutrients
in the upper layers of the soil. Regeneration density may peak during
this period at 30,000 stems/acre or more.
Seedlingsundergodramaticrootandbranchdevelopment.
Competitionduringthisstageisoftenaracetophysicallyoccupy
horizontalandverticalgrowingspace,ratherthandirectcompetition.
Micro-site conditions, weather or mechanical damage, deer browse
andotherfactorsallconspireagainstyoungtrees,resultinginvery
highratesofnaturalmortality.Theresultisthatonlyasmall
percentageofseedlingsactuallysurvive.
Free to Grow Status/Vertical Stratification. Trees that are
present in the main canopy at the time of crown closure result from
seedlingsthathavegerminatedsuccessfully,becomeestablished,and
have had sufficient space around them to grow and develop
competitivebranchandrootsystems.
Limiting Factors

Since the receding of the last Ice Age in North America 10-
12,000 years ago, natural and man-made disturbances, such as
windstorms, floods, fire and clearing, have played a critical role
in the establishment, growth, death and re-establishment of
forests. Forests are not a diorama. Trees grow, reproduce, and
eventually die. Catastrophic disturbances have created the
conditions necessary to perpetuate pioneer species and early
successional habitats. Minor disturbances have permitted a
diversity of age structures and opportunities for species that can
compete in partially shaded environments.
Inforestpreserveswheredisturbanceislimitedtosmallgaps
created by single-tree mortality, species able to establish and grow in
forest shade such as maple, beech, and hemlock are favored. Oak
seedlingsneedhigherlevelsoflighttodevelopintosaplingsthan
commonlyfoundinforestpreserveand/orpartiallycutstands. Thus,
managing a forest as a preserve is an active decision for a gradual
conversion to a forest with more beech and maple. Without
proactiveforestmanagement,(oralargehurricane!)oakswill
graduallydisappearfrommanyofourforests.
Changes in forest composition have been caused by changes in the
typeandintensityofforestdisturbance.Harvestingtreesforforest
productsconstitutesdisturbanceintheforestofanartificialorman-
made nature, and because tree species have adapted to regenerate
successfullyundercertaindisturbanceregimes,harvestingmethods
areoftendesignedtomimiccertainnaturaldisturbances.
Thereis,however,oneveryimportantdistinctionbetweenanatural
disturbance and a timber harvest. When a harvest is planned, the
person who chooses the trees to be harvested has control over
which trees are cut and which trees are left. The success of
regeneration and the future condition of the forest is affected more by
what is left than by what is harvested from a stand. Thus, it is of
criticalimportancetothefutureproductivityoftheforestthatthe
person making these decisions be knowledgeable about species’
requirements.
Soundforeststewardshipisatrueintergenerationalcommitment.
Decisionsmadetodaybylandowners,publicofficials,andforesters
willaffectthecompositionandhabitatdiversityofforeststhatwillbe
enjoyedbygenerationsyetunborn.
Disturbance–The Agent of Change

Mimicking Natural Disturbance. As every avid gardener
knows, each plant species is adapted to thrive in a specific, optimal
rangeofsoilmoisture,fertility,andclimate. Thisconceptlogically
extendstotrees. Atlanticwhitecedarisfoundinswampswithhigh
water tables and chestnut oaks dominate dry traprock ridges,
becausetheyhavetheabilitytocompeteinthoseenvironments.
Pitchpineisendemictosterilesandysoilswhileoptimumsitesfor
sugarmaplearerich,loamysoilswithhighfertility.
Less well appreciated and understood are the adaptations forest
treeshavetodifferentdisturbanceregimes. Disturbanceregimesare
determinedbytherelativecombinationofthreecomponents:type,
intensity,andfrequency. Thesecomponentsareexplainedinmore
detailonthefollowingpages.
Properlyconducted,mostharvestingmethodsmimicanatural
disturbance. Ideally,theforesterwillfirstascertainthelongterm
managementgoalsofthelandownerandthenprepareamanagement
prescription to achieve those goals. An integral part of the
management plan is to determine a species mix to best achieve those
goals. Because each species is best adapted to a specific
disturbanceregime,themanagementprescriptionshouldincorporate
harvestingmethodsthatcloselymimicoptimumdisturbanceregimes
for each species. If the desired species possess strategies for more
than one disturbance regime (e.g., American beech and northern red
oak),theforestercansuggestseveralalternativemanagement
presecriptionstothelandowner.

DisturbanceType.The type of disturbance occurring in a forest
standhasadirecteffectonthesuccessfulsurvivalofregeneration.
Disturbancetypesmayvaryfromthosethatremoveonlythesmallest
trees in the understory (low disturbance), such as in a stand where
grazingispermitted,tothosewhichpredominantlyremovethelargest
trees in the stand, such as a severe wind storm (high disturbance).
Ahigh,oroverstorydisturbance,willdramaticallyincreasethe
amountofdirectsunlightthatreachestheforestfloorandwilloften
increase mineral soil exposure as many trees are uprooted.
Increased sunlight also increases soil temperatures. Large trees can
transpire up to an inch of water per week, thus soil moisture
increasestemporarilywhentheyareremovedbyharvestingor
destroyed by a windstorm.
Alow, or understory disturbance, will also increase the amount of
sunlight(ambientorfiltered)availabletoseedlingsbyremovingthe
shade cast by saplings and small trees. In contrast with high
disturbance,lowdisturbancehasminimalimpactonsoilmoisture,
temperature, and exposure.
LOW(UNDERSTORY)
DISTURBANCE
HIGH(OVERSTORY)
DISTURBANCE

Disturbance Intensity. Disturbance intensity affects the
successofregenerationthroughitsinfluenceonlimitingfactors.
Withinagivenstand,whetherwindthrowormortalityresultsinthe
loss of a single tree, or a large group of trees, seedlings will become
established and grow in those openings. The species that survive and
continuetogrowwillvarydependingontheintensityofthe
disturbance.
Slow,gradualmortalityofindividualtreesfavorsshadetolerant
species (sugar maple, beech) that can germinate and become
establishedintheduff,orundisturbedleaflitteroftheforestfloor,
and compete in the presence of a mature overstory.
A storm microburst that uproots a small group of trees gives the
advantage to species (black birch, red maple) that can become
establishedinpartialtofullsunlightandmaybemorecompetitive
where some bare mineral soil is exposed.
An intense disturbance, such as a crown fire or clearcut, will favor
species (aspen, pitch pine) that are adapted to full sunlight for best
development. These species are unlikely to be able to compete
unlessanintensedisturbanceremovesbothoverstoryandunderstory
trees.
SINGLETREE
DISTURBANCE
STAND REPLACEMENT
DISTURBANCE

Disturbance Frequency.The frequency of forest disturbance
can vary from yearly (single tree mortality), to decades (drought), to
once a century (hurricanes). Indeed, many of the stands in state
forests are currently managed on 100-200 year intervals between
regenerations. Thisissimilartothereturncycleformajorhurricanes
insouthernNewEngland.
In contrast, forests in Connecticut burned an average of once
every 7 years before the 1920s. Before modern forestry practices
became widespread in the early 1900s, many stands were cut every
30-60 years for firewood and charcoal production. Frequent
cuttingsinyoungerstandsofdensesaplingsandpolesforfuelwood
or biomass certainly favors those species that can regenerate rapidly
from root or stump sprouts such as oak and some shrub species
(blueberry).
Speciesthatcompetewellasseedlingsandsaplingsinpartially
shaded conditions, such as red maple and white pine, may benefit
from disturbances every decade or so, in which the upper canopy is
“re-opened” in stages as the mature forest is removed. Examples of
intermediatetermfrequenciesincludedrought,icestorms,andpartial
cutting.
Stands in which disturbances do not occur over long periods of
timeultimatelytendtobecomprisedofmostlyshade-tolerant,
slow-growingspecieswithlonglifespans.Thesespecies,suchas
hemlock, beech and sugar maple create thick dense canopies that
preventsunlightfromreachingtheforestfloor,holdinginthesoil
moisture,andeffectivelyout-competingshade-intolerantspecies.

Forest regeneration methods are based on three premises: 1. Natural disturbances vary in type, intensity,
frequency, and scale. 2. Each species is adapted to, and will regenerate successfully under conditions
created by specific disturbance regimes. 3. Harvesting for forest products is a disturbance.
Therefore, it stands to reason that for a harvesting method to result in successful regeneration of a desirable
speciesormixitshouldmostcloselymimicthenaturaldisturbanceregimeforwhichthedesiredspeciesis
adapted. Because many species possess adaptations for more than one disturbance scenario they can be
expected to have some success regenerating under more than one, or a combination of, harvesting methods.
In light of the long-range management goals and objectives for a forested parcel, as identified by the owner,
whenplanningtoharvestforestproductsaforestershouldrecommendandimplementaharvestingmethodthat
ismostsimilartothenaturaldisturbanceregimesforwhichthedesiredregenerationspeciesaremostclosely
adapted.
Onthefollowingpages,youwillfinddescriptionsofdifferentsilviculturalsystems,orharvestingand
regeneration methods, that are commonly prescribed in Southern New England. They are compared to the
naturaldisturbanceregimestheymimic,andacomparativelistingofmanagementobjectiveconsiderationsis
provided. This listing can be viewed as pro/con or advantage/disadvantage, but that judgment must be made
withinthecontextofclearlystatedmanagementobjectives.
Examplesofmanagementobjectivesforanypieceofforestlandcouldincludesuchthingsas: Maximize
habitat value for game bird; Increase recreational value; Preserve privacy and aesthetic values; and Maximize
periodicincomefromforestproducts
It is readily apparent even from this partial list that two or more of these objectives can be achieved with an
appropriate management prescription. It should also be recognized that some of these objectives might not be
compatible with each other within the same stand of trees or even on the same forested tract. So before
deciding the pro or con of the consequences of any particular harvesting method, the management objectives
and priorities for a stand must be clearly stated.
Forest Management
UNEVEN-AGED
(e.g. forest preserve,
diameterlimit,single-tree
selection)
Trees Sugar maple,American beech, black and yellow birch, eastern
hemlock, basswood, pignut hickory
Shrubs Flowering dogwood, mountain laurel, hobblebush, striped maple,
witchhazel, ferns
Wildlife Pileated woodpecker, flying squirrels,Acadian flycatcher, Cerulean
warbler, Scarlet tananger
Trees Oak, eastern white pine, black cherry, paper birch, white ash, tulip-poplar,
aspen, eastern red cedar
Shrubs Beaked hazelnut, sheep laurel, staghorn sumac, blackberries, blueberries,
sweet fern, huckleberries
Wildlife Red-tailed hawk, indigo bunting, white-tailed deer, eastern bluebird, cedar
waxwing, eastern cottontail
EVEN-AGED
(e.g., shelterwood,
clearcut,coppicewith
standards)

Forest Preserve/Unmanaged Forest. Forest preserves are not
dioramas. Change happens. Where the vegetation remains
unmanagedbyanyhumanintervention,slowchangesaccumulate
graduallythroughthenaturalmortalityofindividualtrees,orsuddenly
andcatastrophicallythroughtheactionofweather,fire,insect
infestation or rampant disease. In the absence of natural catastrophic
disturbances, these forest tracts progress in succession toward a
more shade-tolerant and longer-life-span species mix that tends to
perpetuateitself.
Responsiblestewardshiprequiresthatallforests,including
unharvested forest preserves, have a management plan with a
detailedmap. Ataminimum,managementplansforforestpreserves
includeprovisionsfordeterminingandpermanentlymarkingthe
preserve boundaries to prevent damage to the preserve by
accidentalencroachmentofhumanactivitiesinadjacentparcels.
Where the property abuts a public road, or if hiking trails are
present,provisionsforhazardtreemanagementshouldbeincluded.
Thepropertymapshouldindicatethelocationofotherpotential
hazards (e.g., abandoned wells).
Prioritizingtherelativeimportanceofnaturalfeatureswillfacilitate
objectivemanagementdecisionsandallocationoflimitedresources.
Thisisespeciallycrucialwhenthereisapotentialconflictbetween
priorities(protectionofdeerherdvs.maintenanceofviable
wildflowercommunities).Theplanshouldalsoincludestrategiesfor
monitoringandcontrollinginvasivealienspecies,suchasbarberry
andNorwaymaple,thatcouldthreatentheintegrityofnative
populations.
Advantages
Easytoimplement; Maintainscontinuousforestcover;Higher
number of cavity and den trees; Favors shade tolerant species
(hemlock, beech, maple); Increase in coarse woody debris (snags,
deadlogs);Highwatershedprotectionvalue
Disadvantages
No income for landowner; Change happens, unplanned and
uncontrolled; More prone to some insect and disease infestations;
Lowerdiversityovertime;Shadeintolerantspecieswilldisappear
withoutseverenaturaldisturbance
Forest Management
Unmanaged forest

Single-Tree Selection. Single-tree selection (or simply the
Selection Method) is used by foresters to create or maintain multiple
aged or uneven age conditions in a forest stand. Individual trees that
are mature or declining in health are harvested from the stand in a
mannerthatminimizesdisturbancetotheresidualstand.This
regenerationmethodmostcloselymimicstheprocessesfoundin
unmanaged forests, albeit at an accelerated pace, where trees die
and drop out of the stand gradually. Removals are done on a
periodic basis, so that trees of a variety of age classes are
established and growing in the stand. The openings created for
regeneration,however,tendtoprovide conditionsmostfavorable for
slower-growingshadetolerantspecies.
Landownerswhoconsciouslypracticeunevenagedmanagement
bytheselectionmethodaregenerallymostinterestedinmaintaininga
continuousforestcoverwithtreesofdifferingages.High-value
growingstockcanbeidentifiedandtheirgrowthenhancedthrough
the gradual removal of poorer competing trees. Fast growing trees
andhigh-incomeyieldsaregenerallyalowerpriorityforthese
landowners.Thismethodiscommonlyappliedinsettingswhere
multipleobjectives,suchashabitat,aesthetics,recreation,and
income all must interact. This method should not be confused with
the commonly used and abused phrase, “selective cutting,”
which has no basis in scientific forestry practice or terminology.
See “Diameter limit/High grading.”
Advantages
Maintainscontinuousforestcoverwithlowvisualimpact;
Periodic income for forest owner, albeit low; Favors shade tolerant
species(wheredesired);Abilitytoremovedecliningtrees; Harvest
schedules can be adjusted for market conditions
Disadvantages
Highskillrequiredforsuccessfulimplementation;Highercostsfor
inventory,marking,andharvesting; Mayresultinlowerfiber
productivity/yieldinsubsequentharvests;Willleadtolong-termloss
of diversity; Increased potential of damage to residual trees
Forest Management
Single tree selection

Shelterwood.Asitsnameimplies,thismethodregeneratesanew
forestundertheshelterofoldertrees.Mimickingdisturbancesin
whichonlythehealthiestdominanttreessurvive,thebestgrowing,
mostdesirabletreesinthestandareleftduringtheinitialharvests.
The residual overstory provides the seed source and cover for the
regeneratingforest,whichbecomesestablishedoveranumberof
yearsandwillessentiallybeanothereven-agedforest.
Simultaneouslyextragrowthwillbegainedonthebeststems,
increasingstandvalue.Thelandownerwouldderiverelatively
substantialincomefromeachoftheharvests. However,following
thefinaloverstoryremovalaperiodofnoincomewilloccuruntilthe
newforestisoldenoughfor commercialthinning.
The Shelterwood regeneration method can be applied over two,
three, or more stages, depending on physical, biological and
economicfactors.Thismethoddovetailswellwithrecreationaland
habitat objectives. The initial harvests create a park-like tableau of
majestic trees canopied over a carpet of new regeneration and
wildflowers.
The overstory is harvested in two or three clearly defined stages
scheduled several years apart. The number of overstory removal
stages, and the interval between them, are scheduled according to
the desired regeneration species mix. If, for example, a three-stage
shelterwood system is applied in a stand at 15-year intervals, then
the overstory trees will be harvested over a 30-year time frame, and
the new forest will be almost 30 years old by the time the final cut is
made.
Advantages
Can increase midtolerant (e.g., oak) regeneration; Increased
volumegrowthofresidualtreescanmaintainstandvolumegrowth;
Possiblegeneticimprovementinregeneration;Damagetoresidual
sawtimberusuallyminimal; Increasedverticalstructure
heterogeneity;Regularperiodicincometothelandownerduring
harveststages
Disadvantages
Highskillrequiredforsuccessfulimplementation;Requiresmarket
for smaller trees; Residual volume may be lost to storm damage or
epicormicbranches(watersprouts);Delayinremovingresidualtrees
can lead to loss of midtolerant species and damage to new
regeneration
Forest Management
Shelterwood

Silvicultural Clearcutting. It comes as a surprise to some people
thatclearcutting,whenproperlyplannedandexecuted,isalegitimate
and indispensable regeneration method. There are certain species of
treesthatfullydeveloponlyunderthefullsunlightconditionsfound
afterclearingallcompetingvegetation.Thisgroupofspeciesincludes
tulip poplar, aspen, paper birch, most oaks, eastern red cedar,
butternut,andothers.Withoutclearcuttingorfinaloverstoryremoval
duringashelterwoodthesespecieswillgraduallydeclineand
become rare in most of our forests.
Thereareothersituationswhenclearcuttingisappropriate.
Sometimes a forest stand is in such terrible condition as a result of
insect damage or other past abuse, that it does not fit with the long
range objectives of the landowner. Faced with this situation, a
landowner may be better off to remove the existing stand and start
over.There may also be times when a landowner wishes to convert
an area from one type of species to another (e.g., diversifying habitat
by converting a stand of red maple to eastern white pine).
Regardless of the reason, a clearcut, while perhaps producing a
one-time substantial income for the landowner, sets the forest back
toitsearliestsuccessionalstage.Aclearcutmimicstheconditions
foundfollowingacatastrophicwindstormorfireandprovidesthe
bestcompetitiveadvantagetothespeciesthatrequirefullsunlightto
survive. Regeneration must come as seedlings from a seed source
nearby or from root or stump sprouts. It is important to understand
that for regeneration to be successful complete removal of all
competing vegetation is required. Just removing trees that are most
valuableorlargerthanacertainsizeandleavingtheothersbehind
doesnotconstituteasilviculturallycorrectclearcutsystem.Rather,
thisisacommercialclearcutwithallofitspotentiallynegative
impacts. See: “Diameter Limit/High Grading.”
Advantages
Easiest method to mark and harvest; Necessary to regenerate
shadeintolerantspecies;Highdiversityofgrassesandherbsuntil
crownclosure;Providesearlysuccessionhabitat;Potentially
substantialone-timeincomeforlandowner
Disadvantages
Aestheticallylessdesirableforgeneralpublic;Unacceptablefor
many small forest owners; It costs money to remove residual poles
and large saplings; No income from forest for at least 30-40 years;
Susceptibletosoilerosionifpoorlyimplemented
Forest Management
Silvicultural clearcut

Group Selection/ Patch Cutting. Group selection is a hybrid
incorporatingsomeoffeaturesofboththeselectionandsilvicultural
clearcuttingmethods. Thisapproachdoesnotselectindividualtrees,
ordistributetheintensityoftheharvestevenlythroughoutthestand,
but rather removes groups of trees within pre-defined areas
scattered through the stand. It leaves undisturbed forest in between,
muchliketheconditionsonewouldfindfollowingasevere
“microburst”windevent.Thismethodisverysuitableforcertain
habitat enhancement, and can also be used to create a multiple aged
condition within a forested parcel. Note that proper management
dictates that poorly formed and less valuable trees be cut or
removedalongwiththecommerciallymarketableones.
Agreaterdiversityofregenerationspeciescanresultifthe
patches created are large enough to permit full sunlight to reach the
forest floor in part of the patch, so as to create conditions in which
shade-intolerant species can compete. A good rule of thumb for
shade-intolerantspeciesistomaketheminimumopeningtwiceas
wideasthesurroundingtreesaretall. Thiswillresultinopeningsthat
are at least half an acre in size. Smaller openings (1/4 acre) may be
sufficientformidtolerantspeciesortoreleasewhitepinesaplings.
Aforestmanagedusingthegroupselectionmethodwillsoon
resembleaquiltofmulti-agedandmulti-sizedtrees. Crucialtothe
long-termsuccessofgroupselectioniscarefulplacementoftheskid
trailsandroads.Awell-designedroadsystemwillnotonlylower
harvestingcosts,butprovidesthelandownerwithatrailsystemfor
recreationaluse.
Advantages
Allowsregenerationofshadeintolerantspecieswithout
clearcutting;Provideslandownerwithperiodicincome;Providesa
varietyofhabitatsfromearlytolatesuccessional;Harvestschedules
can be adjusted for market conditions
Disadvantages
Resultingpatchworkforestincreasesmanagementcosts;Patches
maybetoosmallformidtolerant/intolerantspecies;Deermay
concentrate feeding in recent patches; Residual trees near patch
edges may be susceptible to damage
Forest Management
Group selection

Coppice with Standards.The coppice with standards method,
originallydevelopedinEuropetoprovidefuelandwattlefortenant
farmersandtimberforestateowners,maybeusefulforsmall
accessible tracts where a market for fuelwood exists. This system
favors selected crop trees (i.e., standards) for the production of high
valuetimberorveneerlogswhileperiodicallyremovingallother
merchantable trees. Harvests at 10-20 year intervals provide the
landownerwithflexibilitytoaccommodatemarketconditionsand
growth. Reserve trees are kept free-to-grow to obtain maximum
size, provide mast for wildlife purposes, and aesthetic reasons. The
regeneratingforestisprimarilyofsproutorigin,evenagedanddense,
ideal habitat for game birds and other species. Landowners such as
gameclubsandwildlifepreservescanusethismethodeffectivelyto
achieveamixofobjectivesinwhichincomefromforestproductsis
helpful,butotherobjectivesaremoreimportant.Thismethodcan
alsobeappliedeffectivelyinaforestmanagedforfuelwood.The
pleasingvisualmixofmaturetrees,smallsawtimber,andpoleswitha
scattering of shrub patches may make this the ideal method for
landownersdesiringbothcontinualforestcoverandperiodicincome.
Initiatingthistreatmentrequiresselectionofapproximately55
standards (potential crop trees) per acre from existing pole and
sawtimber.The goal is to have an even distribution of diameters over
all classes. At each harvest, eight to ten new standards per acre are
choseninthepolesizeclass.Concurrently,onefifthofthelargest
crop trees are harvested along with all other stems larger than 5
inchesdbh.
Advantages
Maintainscontinuousforestcoverwithlowvisualimpact;
Periodic income for forest owner; Harvest schedules can be
adjustedformarketconditions;Providesregenerationconditions
favoringmidtolerantspecies;Reservetreeswillbeverylargeatend
ofnextrotation
Disadvantages
Highskillrequiredforsuccessfulimplementation;Highercostsfor
inventory,marking,andharvesting;Loweryieldateachharvest
entry; Increased taper of main bole may decrease grade volume;
Large crowns may damage other trees when harvested
Forest Management
Coppice with standards

Reserve Tree/Seed Tree. The reserve, or seed-tree method is like
aclearcut,althoughmoreaestheticallypleasing,inthatnotallthe
overstory vegetation is removed. Borrowing an idea from the
shelterwood method, a few trees are left scattered in the stand to
provide a source of seed. The residual trees should be chosen from
the healthiest and best seed producers in the stand. The main
difference between this and a shelterwood system is that this method
isaveryhigh-intensity,butone–time(lowfrequency)disturbance
event.Alloftheremainingvegetationisremovedatonce,andthe
new forest will be even aged. The reserve, or seed, trees are
retained because other sources for new seedlings may not be
reliable,andgenerallytheyarekeptinthenewstanduntilthetimeof
thefirstcommercialharvest.Thenewforestwillbecomposedmainly
ofoffspringfromthereservetrees,andsomehabitatenhancement
value from retaining these large scattered trees can be realized as
well.
Advantages
Aestheticallymorepleasingthanaclearcut;Providesregeneration
conditionssimilartoaclearcut(i.e.,beneficialformid-and
intolerants); Reserve trees will be very large at end of next rotation;
Provides roost trees for raptors and other birds; Reserve trees serve
as a supplemental seed source, especially for pine and tulip-poplar
Disadvantages
Reservetreessusceptibletowindthrowandlightningdamage
(and lost volume); Crown breakage of reserve trees (see above) can
damage smaller regeneration; Large crowns of reserve trees may
damage other trees during next harvest operation; No income for
30-40 years
Forest Management
Reserve tree method

DiameterLimit/High Grading.All too often a high-grade is
disguised as a “selection” harvest where the most profitable trees are
removedwithlittle,orno,considerationgivenforfutureconditions.
High-gradecutting,regardlessofhow“light”thecutis,hasa
negativelong-termimpactonbotheconomicvalueandonforest
health. Diameterlimitcuttingmayappeartobeasensitivemethod,
cutting the largest trees to release smaller, younger trees.
Landowners are mistakenly persuaded that the largest trees are
overmature and should be harvested before they die. However,
mostlargetreeswithdeep,healthycrownswillnotonlysurvivefor
decades, but, if the stand is thinned, will grow faster and increase in
multiplevalues.Ineven-agedstandsitisthe poorly-growingtrees
that should be removed until the stand can be properly regenerated.
Whereeconomicnecessitydictatesadiameterlimitcutto
generatesufficientincomeforafinancialemergency(e.g.,inheritance
taxes, medical expenses, etc.) the negative impacts can be
minimized. Cutorgirdlealltreeswithpoorformandlowvigor.
Trees with poor form will develop into wolf trees that prevent the
developmentofmorevaluableregeneration. Treeswithpoorform
are also more susceptible to damage from wind, ice, and
snowstorms. Trees with low vigor grow slowly and are susceptible
toinsectanddiseaseinfestations.
Markingadiameterlimitcutissimple. Allmerchantabletrees
larger than a certain diameter are harvested. The landowner may
havetowaitdecadesbeforeanothercommerciallyviableharvest
wouldbepossibleifalltreeswithdiameterslargerthan11inches
wereharvested(acommercialclearcut). Typically,manyofthe
smallerresidualtrees(5-10inchesdiameter)areslowergrowing,
lessvaluablemapleandbirch.
Advantages
Harvestingmethodgenerateshighestshort-termincome;Minimal
skill and cost required; Increased proportion of cavity and den trees;
Increasedverticalstructureheterogeneity
Disadvantages
Long-termlossoffiberproductivityandincreasedharvest
intervals;Increasedproportionofcullandslowgrowingtreesin
stand; Increased potential of damage to residual trees; Loss of
valuablemidtolerantspecies(e.g.,oaks);Detrimentaltowildlife
speciesrequiringearlysuccessionalhabitat
Beware!
Beware!Forest Management
Diameter limit harvest

The following pages outline the general requirements for successfully regenerating some species
groups (e.g., oak, map). The first page of each species group gives some background information on
history, distribution, and mature size. This page also notes the commercial, ecological, and aesthetic
value of the species group. The second page provides information on regenerating selected species.
This section is meant as a general guide and starting point for discussion with a professional forester.
The meaning of the symbols used in this section is given below. Specific guidelines will depend vary by
species (i.e., northern red oak vs. scarlet oak), local soils, and other factors.
Small
mammals
Birds Wind
Seed dispersal mechanisms: Tree species utilize a
variety of mechanism to disperse seed. Some species
spread their seed upon the wind. Other species
depend on small mammals to bury their seed, while
birds carry some seeds great distances.
Reproductive modes: While all trees begin as
seedlings, only the older, established seedlings
(advanced regeneration) of some species can grow
into canopy openings. Some species develop
vigorous, fast-growing sprouts from buds hidden in
stumps and roots.
Light requirements: The relative minimum
requirement for sunlight varies among species.
Tolerant species can survive and grow in full shade.
midtolerants in partial shade, and intolerants only in full
sunlight. Some species require clearcutting to develop
into mature trees.
Special considerations: This section provides
informationonsomeproblemsthatmightbe
encountered when regenerating specific species. For
example,regeneratingoakswillbedifficultinareas
with large deer herds. Species with thin bark are
susceptibletodamagebycarelesslogging. This
woundingincreasesthepossibilityofheartrot.
Seedlings Advanced
regeneration
Stump
sprout
Root
suckering
Tolerant Midtolerant Intolerant Best with
clearcutting
Browsed
by deer
Adapted
to fire
Damaged
by fire
Thin
bark
Insect
problems
Disease
problems
Species regeneration notes

Oaks dominate the landscape throughout most of Connecticut.
Oaks are disturbance-dependent species and most of our oak
forests arose on lands that were repeatedly burned and harvested
prior to 1900. Native Americans would soak the acorns in streams
duringthewintertoremovethetanninsthatmadetheminedible.
Theselarge,majestictreescanliveforseveralcenturies,especially
northern red and white oaks. Mature trees can reach over 120 feet
tall with diameters of 2 feet or more. Northern red oak is
Connecticut’smostvaluabletimbertreeinbothvalueandvolume
(19% of total).
USES
Wood products
Veneer,finefurniture,cabinets,railroadties,pallets,firewood,and
flooring. White and chestnut oak are used to make barrels and ship
hulls.
Wildlife
Acornsareusedbymanyspecies,includingwhite-taileddeer,
turkey, squirrels, chipmunks, and blue jays. White and chestnut oak
acorns, because of their lower tannin content, are eaten before the
acorns of other species.
Aesthetics
The massive trunks and wide spreading branches typical of oaks
lend the forest a gnarly, primeval sense of permanence. The leaves
of scarlet and red oak often create a second peak in fall color during
late October.
Oak (Quercus spp.)

Seed dispersal
Oaks produce large seed crops at 2-10 year intervals. The large
acornsthataredispersedbybluejaysandsmallmammalsgerminate
inthespring.
Reproductive modes
Successfuloakreproductiondevelopsfromstumpsproutingand
fromadvancedregeneration(seedlingswithrootsystemsthatare
5-20-years old).
Light requirements
Althoughoakseedlingscangrowinpartialshade,eventuallyover-
storyremoval(finalstageshelterwood,clearcuttingorpatchcutting)
isrequiredtoachievethefullsunlightconditionsnecessaryfor
seedlings to develop into mature trees.
Site requirements
Northern red oaks grow on good to average quality sites common to
middle and lower slopes. Black and white oaks are on middle
slopes with average site quality. Chestnut and scarlet oaks grow on
low quality sites on upper slopes and ridgetops.
Special considerations
Oaks need protection from browsing where deer herds are large.
Prescribedburningcanenhanceseedlingheightgrowth.
Oak (Quercus spp.)
Best methods successfully regenerate oak
Shelterwood method Reserve tree method

Red maple has become the most common tree in Connecticut,
accounting for one-quarter of all trees. This increase has been
attributed to fire suppression and the increased use of partial cutting
(as opposed to the earlier practice of clearcutting). Their ability to
growinlight(redmaple)toheavyshade(sugarmaple)allowboth
species to persist for decades as small saplings under the shade of
larger trees.
Sugar maple is a long-lived species that can survive for over
300 years, red maple commonly less than 150 years. Sugar maple
is the larger of the two species with mature trees commonly reach-
ing over 100 feet tall with diameters of 2 feet or more.
USES
Wood products
Maplesyrup,furniture,lumber,railroadties,pallets,firewood,
specialtyproducts.
Wildlife
Thelargehollowscommonlyfoundincentenariansarefavoriteden
sites of raccoons, porcupines, and flying squirrels. Chickadees,
wrens, and cardinals eat the seeds and deer will eat the leaves and
twigs.
Aesthetics
The early kaleidoscope of fall colors in red maple swamps herald
thearrivalofautumn. Duringearlyspring,redmapleflowersmist
thehillswithatwinklingofredsandyellows.Sugarmapleisthe
queenofthefallwithleavesturningeveryhuefromclarionyellow
through bright orange to beet red; often with the full range of colors
on the same tree.
Maple (Acer spp.)

Seed dispersal
Sugar maple produces large amounts of winged seeds (samara) at
3-7 year intervals, red maple about every other year. The seeds are
primarilydispersedbythewind.
Reproductive modes
Both species depend on advanced regeneration that develops after
partial cutting or gaps creating by the death of larger trees. Red
maple reproduction can develop from stump sprouts.
Light requirements
Sugar maple is among the most shade-tolerant species in southern
New England. Red maple is competitive in partial shade created by
partialcutting.
Site requirements
One of the reasons that red maple continues to increase in southern
New England is its ability to grow on all but the driest and wettest of
sites. Sugar maple regeneration is found on lower slope positions
where soil moisture is adequate. There is some evidence that its
distributionislimitedbytheamountofcalciuminthesoil.
Althoughloggingdamagerarelykillsmaples,itoftencreateswounds
that cause extensive internal rot. Both species are weakened by
wildfire.
Maple (Acer spp.)
Best methods to successfully regenerate maple
Single tree selection Diameter limit harvest

Eastern white pine can grow on sites ranging from dry ridgetop to
swampy valley. In 1710, the English Parliament passed theWhite
Pine Act to protect the large white pine needed for masts.
Althoughlargelyineffective,thiswasoneofthefirstactsthatset
colonistsandEnglandonacollisioncourse.
This large, majestic species can live for 300-400 or more years.
Mature trees can reach heights of 150 feet with diameters ap-
proaching3feet.
USES
Wood products
Furniture,lumber,barkmulch,shipmasts.
Wildlife
Where eastern white pine is not common, deer will eat needles and
terminalbudsofseedlingsandsaplings. Red-breastednuthatches
both eat pine seeds and nest in cavities. Red squirrels also eat pine
seedsbymethodicallydismantlingthecones.
Aesthetics
Matureeasternwhitepinestandswiththeirmassivebolessoaring
high above inspire a sense of awe and reverence, especially when the
wind whispers through the needles. The green of scattered pines
accentfallcolorsandprovideareminderoflifeduringthemono-
chromemonthsofwinter.
Eastern White Pine (Pinus strobus)

Seed dispersal
Eastern white pine produces large amounts of seeds at 3-10 year
intervals. The seeds are dispersed by the wind in the fall.
Reproductive modes
Successfulwhitepinereproductioncanbeobtainedfromseedlingsin
large openings or clearcuts where a seed source is abundant and
some mineral soil is exposed. Advanced regeneration is more
importantwhenusingmulti-agedstandmanagement.
Light requirements
Althougheasternwhitepineseedlingscangrowinpartialshade,
eventuallyoverstoryremoval(finalstageshelterwoodorclearcutting)
is necessary for seedlings to develop into mature trees.
Site requirements
Eastern white pine can be found in every site from deep sands to
swamps. However, regeneration success is best on sites that are
droughty at some period during the year.
Easternwhitepineseedlingsneedprotectionfromwildfireand
occasionally deer browsing. Ideally, regeneration should be estab-
lished under a partial-shade overstory to reduce pine weevil damage.
Eastern White Pine (Pinus strobus)
Best methods to successfully regenerate white pine
Silvicultural clearcut Reserve tree method

Black birch is often found on average sites, and yellow birch on
moist to wet sites, throughout the state. Black birch is now the
second most common tree species in Connecticut. Both species
containoilofwintergreen,methylsalicylate,whichgivesbirchbeer
itsdistinctivetaste. Thepresenceofthischemical,poisonousathigh
doses, provides some protection from deer browse damage.
Many of the larger black birch trees have one or more large cankers
thatreducethepotentialeconomicvalueofthisspecies. Although
both species can survive for 200 years, maximum ages of about 120
are more typical. Mature trees are commonly 80 feet tall, with
diametersslightlylargerthanafoot.
USES
Wood products
Veneer,lumber,railroadties,pallets,andfirewood.
Wildlife
The seeds of these trees provide some winter food for chickadees,
ruffledgrouse,andchipmunks.Thebarkofyellowbirchisutilized
fornestingmaterialbysomebirds.
Aesthetics
Thegoldenfallfoliageofbirchleavesaddsgaietytoautumnland-
scapes.Thefrilly,peelinglight-coloredbarkofyellowbirchisa
uniquefeatureofmoistwoodlands
Birch (Betula spp.)

Seed dispersal
Black and yellow birch produce large amounts of seeds at 1-2 year
intervals. The small seeds are dispersed 300 feet or more across
crustedsnowbythewindinmidwinter.
Reproductive modes
Successfulbirchreproductioncanbeobtainedfromseedlingsinlarge
openings or clearcuts. Black birch can also produce successful regen-
eration in openings created by shelterwood operations.
Light requirements
Althoughbirchseedlingscangrowinpartialshade,overstoryremoval
or death is necessary for seedlings to develop into mature trees.
Site requirements
Blackbirchiscommonlyfoundonaveragequalitysites;yellowbirch
on moister sites. In the northern part of the state, black birch is found
towards ridgetops and yellow birch on midslopes.
Bothblackandyellowbirchareverysusceptibletofireandlogging
damage. Although nectria canker is common on black birch and can
makethewood unmerchantable,itrarelykillsseedlings.
Birch (Betula spp.)
Best methods to successfully regenerate black and yellow birch
Commercial clearcut Group selection

Beech is a common species in forest preserves and high-graded
stands. It is a slow-growing, long-lived species (when not infested
with beech bark disease), and is our most shade-tolerant hardwood.
Saplings can survive for 100 years or more in the understory before
reachingtheuppercanopy.Unfortunately,anintroducedinsect/
disease complex, beech bark disease, has killed and weakened
beech across a large part of the eastern United States. In the
absence of beech bark disease, trees can survive for several centu-
ries. A mature beech can approach 100 feet in height with diameters
of 2 feet or more. Because beech has a tendency to root sucker,
what appears to be a small beech grove is often an extended clone
USES
Wood products
Furniture, chopping blocks, baskets, railroad ties, pallets, and
firewood.
Wildlife
American beech seeds provide food for large animals such as black
bears and small animals such as white-footed mice. Avariety of
birds also eat the seeds.
Aesthetics
Thedistinctsmoothbarkisaneasyidentifierforbeech.Young lovers
havebeenknowntocarvetestimonialstotheireverlastingdevotion
in the bark of beech trees, though whether this contributes to the
aesthetics is questionable. Few herbaceous plants grow in the deep
shade of a beech grove providing the forest, in the absence of beech
sprouts, with an open, “shady glade” appearance.
American Beech (Fagus grandiflora)

Seed dispersal
American beech produces large seed crops at 2-8 year intervals.
The medium sized seeds are dispersed by blue jays and small
mammals.
Reproductive modes
Successful American beech reproduction develops from root suck-
ers and advanced regeneration. Beech seedlings can persist in the
understory for decades.
Light requirements
American beech is among the most shade tolerant species in south-
ern New England and can develop in all but the darkest shade.
Site requirements
Americanbeechregenerationisfoundonmidslopepositionswhere
soil moisture is adequate. It is also found on lower slopes and
benches.
Loggingdamagecancreatewoundsthatcauseextensiveinternalrot.
Beech bark disease can stunt growth of saplings and causes de-
formedgrowth.
American Beech (Fagus grandiflora)
Best methods to successfully regenerate American beech
Single tree selection Unmanaged forest

The ConnecticutAgricultural Experiment Station (CAES) prohibits discrimination on the basis of race, color, ancestry,
national origin, sex, religious creed, age, political beliefs, sexual orientation, criminal conviction record, genetic information,
learning disability, present or past history of mental disorder, mental retardation or physical disability including but not
limited to blindness, or marital or family status. To file a complaint of discrimination, write Director, The Connecticut
Agricultural Experiment Station, P.O. Box 1106, New Haven, CT 06504, or call (203) 974-8440. CAES is an equal opportunity
provider and employer. Persons with disabilities who require alternate means of communication of program information
should contact the Station Editor at (203) 974-8446 (voice); (203) 974-8502 (FAX); or paul.gough@po.state.ct.us
Photo Credits t-top photo, m-middle photo, b-bottom photo
J.P. Barsky: 11m. 14mb, 17t, 22m, 25b, 26b, 27b, 30b, 32b, 34tb, 36t, 38tm, 40t, 42tm; Fred Bormann: 10mb
CAES historical archives: 4tm, 5m,b, 6t, 10t, 7t, 19b, 20m, 23t; CTDEP, Division of Forestry: 20m, 22t
Sharon Douglas: 23m; Martin N.P. Gent: 2t; Paul Gough: 36m; Uma Ramakrishnan: 9m; Joel Stocker: 11t; Heidi Stuber: 6m;
USDA Forest Service, 23b; Thomas Worthley: 8t; Jeffrey S. Ward: all other photos
A special thanks to Hull Forest Products for permission to photograph their mill operations (page 11). We would also like to
thank J.P. Barsky, M.J. Bartlett, G. Milne, D. Beers, and J.E. Gillespie for their helpful comments
An expanded version in electronic format is available at:
www.canr.uconn.edu/ces/forest
www.caes.state.ct.us/specialfeatures/specialfeatures.htm

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